The present invention generally relates to a method of producing low calorie margarines having an extra low fat content, for instance a fat content 5 of between 15 and 38 percent by weight. The invention also relates to an extra low calorie margarine manufactured accordingly.
A method for the manufacture of such margarines is known from the Swedish patent 461.762 (corresponding to U.S. Pat. No. 4,978,554) in which method a protein containing water phase is emulsified in a fat phase to directly form a water-in-oil emulsion, which is pasteurized, cooled and packed, and in which the water phase is prepared:
in a first stage, in that starch and an emulsifier are solved in skim milk, butter milk, whey, water or mixtures thereof, under stirring; the emulsifier in the water phase is used for preventing the starch from becoming gelified; PA1 in second stage, in that the starch-emulsifier solution is allowed to stand and swell and become "ripened" for some time, for instance for about 24 hours; PA1 and in a third stage in that the "ripened" starch-emulsifier solution is mixed with a protein concentrate from a milk product, with melting salts and with taste-giving substances to form a final water phase; PA1 whereupon the ready water phase is successively emulsified in a fat phase prepared in a conventional way; PA1 and the water-in-oil emulsion thereby formed is pasteurized, cooled and packed.
The said known method of manufacturing the extra low calorie margarine is expensive, there is a need for a special manufacturing equipment and a special plant for manufacturing same, and the process is rather complicated and time consuming.
The preparation and the handling of the protein material is expensive, since the preparation thereof necessitates a fermentation of the milk product and a precipitation and a separation of the protein. Also, there is a lack of protein on the market and therefore it would be good to reduce the amount of protein used for the manufacture of the actual margarine.
Further the handling of the starch is expensive depending on the time consuming and relatively complicated handling as far as to a ripened condition of the starch solution. In case of normal handling of highly concentrated starch there is a risk that the starch will gelified when a warm starch solution is being cooled, and this is not wanted. Thus, the starch solution is not "stable in solution". In the above mentioned known method such gelification is prevented in forming a starch lipid complex by adding emulsifiers of the monoglyceride type to the starch solution.
A process for producing a low fat spread is known from U.S. Pat. No. 4,536,408 (MOREHOUSEJ, in which there is used starch in the form of maltodextrine having a so called D.E. (dextrose equivalent) value of between 4 and 25, which corresponds to molecular weight of between about 650 and 4.050 and an average polymerization degree of between 4 and 25. By dextrose equivalent (D.E.) is meant the reducing ability of the starch as compared with that of pure dextrose. The D.E. value also is figure of the tendency of the starch to react with proteins. A low D.E. value means a low tendency of the starch to react with proteins.
Such a relatively high D.E. value is not very good for producing a low calorie spread in several respects. The starch has a tendency to gelified, in particular if the margarine is stored for some time, and a gelified margarine is considered useless; depending on the low polymerization degree the starch has a rather poor water binding ability, and therefore there is a need for adding a relatively high amount of starch in the margarine; there are generally difficulties in directly providing an emulsion of the water-in-oil type, and mainly it is necessary to first provide an o/w emulsion, which is cooled and is further worked until phase inversion occurs to the intended w/o emulsion; the high amount of starch gives the margarine a not wanted high nutritious value; the high amount of starch also gives the product a not wanted sweet taste; starch having a relatively high D.E. value may, in combination with protein in the margarine product, discolor the protein into a brownish color and may give the margarine an undesired disflavour.
Summarizing there has been a wish to reduce the number of persons needed for the manufacture of the margarine, and to be able to use a less skilled staff; to reduce the total handling time, to get a simpler and thereby cheaper handling process for the product; to reduce the necessary storing time and get reduced storing costs of the ingredients, in particular of the starch part thereof; to reduce the amount of protein used in the margarine; to avoid the use of emulsifiers in the water phase, and to reduce the waste material in the manufacture of the margarine.
It has proved possible to meet all of the above listed requirements by using a type of starch which is pre-treated in a factory, and which is used in the manufacture of the margarine in the dairy or the margarine factory without the need of further treating the starch.